F-35 versus Eurofighter for the UK

The F-35 compared with other modern jets.
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LowObservable

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Unread post04 Jul 2008, 17:01

Beazzz wins the Internetz today for out-of-control thread drift, and for irritating Obamanite.

Obamanite, you troll: Do you want to cite something specific in that comment that you feel cannot be justified from a reputable source?
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sferrin

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Unread post04 Jul 2008, 17:33

Scorpion82 wrote:Well the RAF needs a 232 force to maintain a 140 force for the intended period of time.


And the USAF wants 381 F-22s so it can keep 240 ready to go into combat. Makes you wonder how many of 183 would be avaliable? Not too many. :cry:
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Unread post04 Jul 2008, 22:57

Obamanite wrote:Goes to show, I don't know anyone who doesn't accept evolution as scientific fact. I guess these kinds of things depend on the region of the country one's from and whether your mom is also your sister and your grandad's your dad. Phew, glad I came from a monkey instead :wink:


I had respect for your posts...buts thats all gone now.
“Its not the critic who counts..The credit belongs to the man who does actually strive to do the deeds..”
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Unread post05 Jul 2008, 14:15

I guess you have to have a lot of faith in Intelligent Design when you work on the F-35...

And pray that there's intelligent life somewhere up in space, 'Cause there's ****** all down here on Earth.

- Monty Python

So if Lockheed Martin is the Supreme Being, then what is the F-35B?
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DarthAmerica

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Unread post05 Jul 2008, 15:34

LowObservable wrote:The key is that the F-35 is either LO, or it's not. If it's LO it has a defined and funded maximum of four AIM-120s, the internal ASRAAM option being dead. With four AIM-120s the only option is to decide the fight in LO mode - once you're detected, the disadvantages of having no HOBS, LOBL or IR missile capability and F-16-like maneuverability and acceleration will rapidly tip the fight in favor of (say) an Su-35. The weight and wing area numbers don't tell lies.


Alright now. Time to take this one apart. LO a suggestion for the future would be to use some data to back up your claims. It would better help you to catch your mistakes and eliminate the need to debate when you are correct....

....Radar cross sections are not a binary value. It's not one or off. It's a analogue thing until the ADC gets involved after the tx. Fighters like the Mig-21, F-16 and F/A-18C are known to have lower RCS than larger fighters. A more specialized fighter like the F/A-18E has an even lower RCS. Why do you think that is? And how do you think that RCS compares to something like the Su-27 which is a HUGE radar target?

http://www.suchoj.com/ab1953/Su-27/riss/Su-27_05.jpg

A radar head on can see and count a Su-27s compressor and stator blades. It's highly likely that even a F-35 carrying external ordinance would have a detection range advantage over an Su-27. Remember as well the F-35 is carrying a far more capable AESA radar.

People on the internet and usually with little or no knowledge of combat keep lamenting about 4 AAMs. Yet they can't cite any examples of where 4 AAMs has ever been a serious limitation. A clear misunderstanding. Nobody ever says that the S-300 which has a 4 round TEL doesn't have enough missiles but somehow this is a crucial disadvantage for the F-35. LO, here is a hint for you. When you see pretty pictures of combat aircraft flying around with 10 AAMs. Thats usually just for show. Thats not normally how they fly because it causes severe drag penalties and there just isn't time or fuel to engage that many targets in a dogfight.

You also mention aircraft weight and wing area more commonly known as wing loading. You go on to suggest the F-35 is somehow deficient when in fact it is designed to meet or exceed the performance of the F-16 which is highly regarded for it's maneuverability. Did you know that the F-16 and F-35 have very similar wing loadings? What do you think that means? The difference of course being that an F-35 has much less drag and an engine almost twice as powerful. Think about that.

http://en.wikipedia.org/wiki/F-35_Light ... ning_II.29
http://en.wikipedia.org/wiki/F-16_Fight ... lock_30.29

Lets look at the Mig-29's and Su-30MKI(a real operational Flanker variant) wing loading:

http://en.wikipedia.org/wiki/MiG-29#Specifications
http://en.wikipedia.org/wiki/Sukhoi_Su- ... u-30MKI.29
http://en.wikipedia.org/wiki/Su-35#Spec ... 28Su-35.29

The F-35 isn't going to have any maneuverability issues.

Also, how come you made no mention of the Su-27's center fuel tank? Do you know what I'm referring to? Well when you see a Sukhoi awing some crowd at an airshow with amazing airshow tricks. You do know it is not flying around combat configured with weapons or fully fueled right? A combat loaded Su-27 would be a completely different animal in terms of maneuver vs any variant you have seen on YouTube doing "tricks". Not that any of that matters much in an era of modern missiles. You will notice that I didn't mention the Su-35 in my analysis. Do you know why? Because it is only a prototype and not an in service combat jet. So you are using a fighter that doesn't really exist as the baseline for your threat matrix. Do you understand what that says about your credibility and knowledge of the subject matter?

http://www.acig.org/artman/publish/article_288.shtml

The limiting factor is not detection range but missile range. Missile launch will be detected and probably located (networking between the hostiles, with two MAWS bearing lines) and even if the hostiles don't know specifically who's been targeted they know the approximate arrival time and when to punch chaff, turn and run downhill, weaving like an SOB. This runs your AMRAAM out of juice pretty fast unless you launched it at M=1.7 and 65,000 feet. How close do you have to get to achieve a decent Pk in that situation? Way less than published max range. And if you don't kill all the enemy (assuming them to be Su-35s) can you now avoid the visual fight? How good is your IR suppression? Are you now inside IRST detection range?


Networking between hostiles? Are you making that up? I've never heard of any Su-27 or any other threat aircraft that share MAW RWR data. Look at 3-D trilateration or multilateration then look into AESA and LPI. I think you may also want to look at how a GPS works to get an idea of what it would take to make that work. Again, you need to stop mentioning the Su-35 if you wish to be taken seriously.

http://en.wikipedia.org/wiki/Multilateration
http://en.wikipedia.org/wiki/Trilateration

You further demonstrate that you don't know what you are talking about when you say missile range is the limiting factor. Nothing could be further from the truth. One of the benefits of the F-22, F-35, F/A-18E/F and some F-15C's AESA are that they can actually see far out enough now to use an AIM-120 to it's potential against a fighter sized or cruise missile target. An AESA equipped F-35 will "see" a threat well outside of missile range and can lob a missile to meet that threat at the very maximum kinematic range of the weapon. Legacy radars weren't nearly as capable.

Just doing some basic math, let see what this could mean. An F-35 detects a Su-27 well beyond the AIM-120 range. For sake of argument lets just say its 50km range for an AIM-120. That's about a 60 second flight considering the missile doesn't actually make a beeline toward the target but rather uses a semi-ballistic trajectory. Depending on the target speed that could add 15 to 30 km of range! That right there almost covered the launch envelop of most threat BVR AAM NEZ. Especially when you are dealing with an LO target that you probably could not detect even if you were 30km away from it. These are just simple calculations but it illustrates the point. See the link below.

http://findarticles.com/p/articles/mi_p ... _390983136

A US JSF will be in better shape than an export JSF, because it has better LO (this is now beyond dispute) and AIM-120D, which was designed to deal with this problem but is not even discussed for export. And remember that the "Super Flanker" threat was assessed many years ago and the answer was the F-22.


Prove that the LO features of any F-35 user will be better than others. Also, export F-35s will also be able to use METEORs so lack of AIM-120D isn't even an issue. Again no further comment on this "Super Flanker" fanboy nonsense.

http://www.defenseindustrydaily.com/met ... -f35-0599/


If you go non-LO, the F-35 has now defensive EW except a potential X-band jammer. Its performance characteristics are not optimized for a maneuvering BVR fight (that is, weak supersonic maneuver, less speed and altitude). In that kind of serious fight, too, the Typhoon will punch tanks.


Do you even do basic research? Look at BAE IEWS. Regarding speed and altitude. You do know the F-35 has an afterburner and can carry up to 18000lbs+ of fuel and still be aerodynamically clean don't you? Do you know what that means? Here is a hint, it's essentially for practical purposes no slower than any other non-F-22/Mig-31 and for a longer time.

http://www.allbusiness.com/government/g ... 902-1.html

Well, yes... because that's what the F-35 was designed to do. The European philosophy - because in the 1980s there was no way (there still isn't IMHO) to combine everything else with LO without building an F-22 - was to develop LO high-precision cruise missiles, launched from fighters, to penetrate the toughest threats.


Why then are they buying F-35's IN BULK?


Not exactly. That would be saying that the Typhoon configuration was laid out and its engine selected in 1976.


The Typhoon is a 1970's design realistically. You can arguably say that it's 1980's technology since things weren't finalized until the 1980's. But it is at least a 20 year old design.

OK, I sources all the major claims with numerous links LO. PLEASE, PLEASE, I'm begging you. If you are going to respond other than to concede that your analysis is flawed, SOURCE your response and use some numbers. No one want's to read a bunch of unverifiable "opinions" or wild claims.


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Unread post05 Jul 2008, 16:27

Darth

I stand utterly refuted by someone who regards Wikipedia as an authority.

The statement that "the F-35 is either LO or it's not" is of course a direct reference to statements by LockMart people - to paraphrase, "if you see an aircraft with external stores it's not stealth." Broadly speaking, that's correct.

In more detail, yes, you can adjust RCS inside those broad bands. However, you appear to be blissfully unaware of the papers issued by ITAE on RCS reduction measures for the Sukhoi family. Try googling "itae rcs sukhoi" for sources other than Wackypedia.

I'd agree that I can't cite examples of a case where four AAMs has been a serious limitation. Nobody can, mainly because there has never been a real-world, high-end peer-versus-peer air battle in recent history. But the people who designed every fighter with a primary air to air mission since 1970 (including the F-22) with six to eight AAMs are clearly not as smart as you. Maybe they should toss out all that mission analysis and check Wikipedia instead.

The F-16 is indeed highly regarded for its maneuverability. The F-22 and Typhoon, in particular, are designed to extend that maneuverability into the transonic/supersonic realm. The F-35 is not - read the requirements. And if you look at the Wackypedia post you cite on the JSF wing loading, and do some sums like you were taught in third grade (you did finish third grade?) you will see that the posted take off weight that's used to calculate wing loading is massively wrong. At that weight the jet doesn't have full tanks, let alone weapons.

No, I really thought that the Su's at air shows were fully loaded. And the Su-35 is "only a prototype" that "doesn't really exist"? At least it's gone supersonic, and are you saying that it can't make it into service before JSF?

Oh cool, a link to a gamer site. Now that's authority.

"I've never heard of any Su-27 or any other threat aircraft that share MAW RWR data."

Then you've never heard of the Gripen. Or the F-22. Granted it's not a total solution, but there ain't no such thing as a stealth AMRAAM.

On missile range: please let the US Navy know, too, that they can stop wasting money on the AIM-120D. Why does the Super Hornet need an extended-range missile? Why is Meteor being developed? Why does the USAF require a Mach 1.7/65,000-foot launch for AMRAAM? Are you saying that none of these things are happening?

Super Flanker "fanboy nonsense"? Now you're graduating from obtuse to insulting. And export F-35s will have Meteors when someone pays for it, not before. As for the export question, I have closely tracked, over the years, attempts to get anyone involved in JSF to state that they will all be identical in signature terms, and the simple question is always stalled or evaded.

I should have written "active EW". My mistake.

I know about the JSF's perfomance characteristics, but unlike you I do not believe Wikipedia and I can do math. I would also (again) advise you to check the actual requirements to which JSF was designed.

Again, sorry: I should have said "the philosophy behind the Typhoon, Rafale and Gripen".

The points above, you note, are cited on checkable real-world evidence. The capabilities designed into the AIM-120D or F-22, for example, are factual, and there's only one valid reason for them. There are a lot of sources out there that will describe the status of the Su-35 and none will suggest that the aircraft cannot match the IOC of the F-35.

Wikipedia, Schmikipedia. If anyone produced a report for me that depended on Wikipedia for anything other than background, I'd have him flogged.
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Unread post05 Jul 2008, 16:32

DarthAmerica wrote: LO, here is a hint for you. When you see pretty pictures of combat aircraft flying around with 10 AAMs. Thats usually just for show. Thats not normally how they fly because it causes severe drag penalties and there just isn't time or fuel to engage that many targets in a dogfight.


Well I suppose you have never seen the operationally flying F-15s, Tornado ADV or Su-27 with 8-10 missiles? I of course understand your point that such a number of missiles isn't really required in smaller conflicts or if you just have the quantity of platforms you don't need such a quantity of missiles on each platform, but it's a fact that aircraft were and are flying with such larger load of AAMs not just for airshow purposes.

You also mention aircraft weight and wing area more commonly known as wing loading. You go on to suggest the F-35 is somehow deficient when in fact it is designed to meet or exceed the performance of the F-16 which is highly regarded for it's maneuverability. Did you know that the F-16 and F-35 have very similar wing loadings? What do you think that means? The difference of course being that an F-35 has much less drag and an engine almost twice as powerful. Think about that.


Well which version of the F-16 are you comparing? Earlier models had a noticeably lower wing loading than the F-35, while there engine thrust was just about 50% as you said. For later examples (which are known for being less maneuvreable) might have a similar wing loading (I'm to lazy to do the math to be exact), but in that case their engine thrust is already ~30% better.

The F-35 isn't going to have any maneuverability issues.


Well the F-35s maneuvrability will at least be sufficient, but it's not all that important for this aircraft. The F-35s primary mission is AG and in the AA role its strength is the combination of LO, sensors and MMI (SA superiority).

Also, how come you made no mention of the Su-27's center fuel tank? Do you know what I'm referring to? Well when you see a Sukhoi awing some crowd at an airshow with amazing airshow tricks. You do know it is not flying around combat configured with weapons or fully fueled right?


You seem to have missed the airshow demonstration of the Su-30MK (no.603) in 1994. This aircraft was flown with full weapons load exactly for the reason to demonstrate that it's not just an airshow performance. But you might be right about the fuel load what sets that in relation.

You will notice that I didn't mention the Su-35 in my analysis. Do you know why? Because it is only a prototype and not an in service combat jet. So you are using a fighter that doesn't really exist as the baseline for your threat matrix.


The F-35 isn't operational either so that's a somewhat moot point. Though we can probably agree that while the F-35 is relative safe to be operational at some time in the future, while the Su-35 has an uncertain future at all. But I would tend to say that the Su-35 in its current form is even further developed, meaning closer to an operational platform than is the F-35.

http://www.acig.org/artman/publish/article_288.shtml

You further demonstrate that you don't know what you are talking about when you say missile range is the limiting factor. Nothing could be further from the truth. One of the benefits of the F-22, F-35, F/A-18E/F and some F-15C's AESA are that they can actually see far out enough now to use an AIM-120 to it's potential against a fighter sized or cruise missile target. An AESA equipped F-35 will "see" a threat well outside of missile range and can lob a missile to meet that threat at the very maximum kinematic range of the weapon. Legacy radars weren't nearly as capable.


Well I don't think it's just limited to the platforms you mentioned, but LOs point is somewhat valid. The problem is if you detect an enemy at lets say 150 nm, but you have to close to 25-30 nm (generic value) to launch your missile, the missile's range is indeed a limiting factor.

Just doing some basic math, let see what this could mean. An F-35 detects a Su-27 well beyond the AIM-120 range. For sake of argument lets just say its 50km range for an AIM-120. That's about a 60 second flight considering the missile doesn't actually make a beeline toward the target but rather uses a semi-ballistic trajectory. Depending on the target speed that could add 15 to 30 km of range! That right there almost covered the launch envelop of most threat BVR AAM NEZ. Especially when you are dealing with an LO target that you probably could not detect even if you were 30km away from it. These are just simple calculations but it illustrates the point. See the link below.


Basically agreed, but you have to take into account that such a "long" range shot would require the launch platform (F-35 in this case) to fly high and fast enough increasing the risk of detection in the IR spectrum by the lack of sufficient supercruise speed, meaning the afterburners are used. At higher altitude the signature will also increase. That's of course no guarantee that an IRST will detect it early enough just a thought. BTW the often mentioned LPI is no guarantee either not to be detected a makes things just more difficult.

The Typhoon is a 1970's design realistically. You can arguably say that it's 1980's technology since things weren't finalized until the 1980's. But it is at least a 20 year old design.


It's more an 80s design with 90's+ technology being used, very much like the F-22. It's true that first thoughts and even concepts occured during the 70's, but what eventually become the Typhoon was defined in the 80's.
Last edited by Scorpion82 on 05 Jul 2008, 16:49, edited 1 time in total.
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Unread post05 Jul 2008, 16:38

Edit:
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DarthAmerica

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Unread post05 Jul 2008, 17:04

LowObservable wrote:Darth

I stand utterly refuted by someone who regards Wikipedia as an authority.


Whats funny is that is actually what happened. Again, you are a demonstrated incompetent with regard to this subject matter. My choice of sources and websites was intentional. Again, right over your head. Look, when you can respond with a bit of competency or be humble enough to ask questions perhaps I'll go more into details but I've given more than enough information to you for you to figure out where your facts are incorrect.

Just to give you an idea of what I mean when I say competency. You mentioned again the Su-35 and said it's much closer to being IOC than the F-35. That is laughable. Russia could never keep up with the F-35 rate of and diversity of production. NEVER. By 2013-2016 there would be 2 to 3 times more F-35s, in 4 to 5 times as many air forces which are far superior flying to anything Russia could ever produce even at full capacity. Why don't you take a look at the rate of production and delivery schedules for the Su-27 to get an idea of what I'm talking about.

LO again, stop destroying your credibility while you can.


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Unread post05 Jul 2008, 17:22

Proverbs 17:28


"Demonstrated incompetent with regard to this subject matter." That's new to me, and really quite amusing.

Youy may end up owing sferrin a new keyboard.

As for the Su-35, we'll see what happens; but as a major derivative, rather than a new aircraft, history would suggest that as long as the money flows in, it won't take as long as an all-new platform; and I'd argue that as a threat benchmark over the life of the program, it's a reasonable choice. And (as usual) most of your comments are about production rate, which was not what I was talking about.
Last edited by LowObservable on 05 Jul 2008, 17:37, edited 1 time in total.
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Unread post05 Jul 2008, 17:34

Scorpion82 wrote:Well I suppose you have never seen the operationally flying F-15s, Tornado ADV or Su-27 with 8-10 missiles? I of course understand your point that such a number of missiles isn't really required in smaller conflicts or if you just have the quantity of platforms you don't need such a quantity of missiles on each platform, but it's a fact that aircraft were and are flying with such larger load of AAMs not just for airshow purposes.


What I've seen is aircraft carrying 2 to 4 AAMs IN COMBAT. Don't forget that the F-35 can carry more than that if required and still keep considerable advantage over any fighter short of the F-22.


You also mention aircraft weight and wing area more commonly known as wing loading. You go on to suggest the F-35 is somehow deficient when in fact it is designed to meet or exceed the performance of the F-16 which is highly regarded for it's maneuverability. Did you know that the F-16 and F-35 have very similar wing loadings? What do you think that means? The difference of course being that an F-35 has much less drag and an engine almost twice as powerful. Think about that.


Well the F-35s maneuvrability will at least be sufficient, but it's not all that important for this aircraft. The F-35s primary mission is AG and in the AA role its strength is the combination of LO, sensors and MMI (SA superiority).


Which gives it a considerable advantage.


You seem to have missed the airshow demonstration of the Su-30MK (no.603) in 1994. This aircraft was flown with full weapons load exactly for the reason to demonstrate that it's not just an airshow performance. But you might be right about the fuel load what sets that in relation.


The fuel situation is a matter of physics. Indisputable.


The F-35 isn't operational either so that's a somewhat moot point. Though we can probably agree that while the F-35 is relative safe to be operational at some time in the future, while the Su-35 has an uncertain future at all. But I would tend to say that the Su-35 in its current form is even further developed, meaning closer to an operational platform than is the F-35.


See my previous post.

Well I don't think it's just limited to the platforms you mentioned, but LOs point is somewhat valid. The problem is if you detect an enemy at lets say 150 nm, but you have to close to 25-30 nm (generic value) to launch your missile, the missile's range is indeed a limiting factor.


No, it's the sensor. Why do you think prior aircraft were very much tied to AWACS and GCI to maximize effectiveness. It's because on their own they don't have the situational awareness to set up attacks in the most advantageous way. Why do you thing getting AESA compatible aircraft is a # priority these days. Please, nobody respond with the suggestion that I'm saying AESA fighters makes AWACS and GCI obsolete.


Basically agreed, but you have to take into account that such a "long" range shot would require the launch platform (F-35 in this case) to fly high and fast enough increasing the risk of detection in the IR spectrum by the lack of sufficient supercruise speed, meaning the afterburners are used. At higher altitude the signature will also increase. That's of course no guarantee that an IRST will detect it early enough just a thought. BTW the often mentioned LPI is no guarantee either not to be detected a makes things just more difficult.


Wrong. Has nothing to do with flight performance. Think of how an ASAT works. A DDG can fire at targets well outside the range of an SM-3. It doesn't supercruise either. Understand now?

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Unread post05 Jul 2008, 18:14

LowObservable wrote:"I've never heard of any Su-27 or any other threat aircraft that share MAW RWR data."

Then you've never heard of the Gripen. Or the F-22. Granted it's not a total solution, but there ain't no such thing as a stealth AMRAAM.



Overlooked this one. LO I did say "Su-27 or Threat" aircraft which the F-22 and Gripen are not.

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Unread post05 Jul 2008, 19:15

Well which version of the F-16 are you comparing? Earlier models had a noticeably lower wing loading than the F-35, while there engine thrust was just about 50% as you said. For later examples (which are known for being less maneuvreable) might have a similar wing loading (I'm to lazy to do the math to be exact), but in that case their engine thrust is already ~30% better.


I don't think you can compare the "wing loading" on two modern fighter aircrafts and conclude on the amount of lift available or their turning potential under any conidition. This is so because the "wing" is not the only thing that produces lift, and wing area is not a good indication of the size of the "wing" to begin with. Sounds like bullshit? Read on...


Total lift is generated by the entire aircraft not the "wing".

If you chop the right wing completely off an F-35 in flight, it can probably stay level and maybe even land! This is so because the body itself -- especially one with a broad, flat bottom and a curved upper surface like the F-35's -- is in itself a wing. An Israeli F-15 had its right wing cleaved off in a mid air collision. The wing was completely gone at the root, but the pilot is able to level the aircraft and land successfully albeit at dangerously high landing speeds. Why? Because the body itself is providing a enough lift -- enough to balance the left wing and keep the aircraft flying.

http://video.google.com/videoplay?docid ... SqDw&hl=en

If you look at an F-35 cruising in flight, you will notice that the horizontal tails are deflected slightly upwards and providing lift. This is because the center of lift of the aircraft (minus the tail) is actually a tad behind the center of gravity. Unstable aircrafts are like that -- without lift from the tail, the natural tendency is to pitch up and flip backwards. Now, if you look at the position of the landing gear and its location in relation to the wing, you'll notice that the landing gear is located in in front of most of the wing and the center of gravity MUST be ahead of the landing gear (or the aircraft will tip over and sit on its tails on the ground). Now, if the center of gravity is ahead of practically the entire wing, why is the the F-35 "unstable" and why is the tail providing lift in flight? Answer: Because the body itself is also providing a considerable amount of lift and this is centered well ahead of the center of gravity such that the total lift is center ahead of the center of gravity. [see photos]

Center of gravity has to be somewhere in the green box ahead of the green line (landing gear line).
Center of Lift has to be somewhere in the red box and ahead of the center of lift for an unstable design.
The yellow area denotes the wing; notice that the center of lift is well ahead of any plausible location for total lift generated by the wing alone. This is not possible without significant body lift contribution.

Image
Note the upward cant of the tail in flight indicating -- typical attitude of unstable aircrafts in flight.
Image
An outline of the whitcomb supercritical airfoil super imposed on the F-35 note the contour similarities between the Lightning II's fuselage and the airfoil?
Image


Wing Area is not a good indication of wing size.


Wing Area is defined as the planar area you get when you extend the leading and trailing edges of the wing to the center line. It can include areas that is the fuselage or even empty space! For a given actual size of the wing, you also get more wing area if you have a lot of positive sweep on the leading edge and a lot of negative sweep on the trailing edge. This is so because you'll then cover a lot of area which is NOT the wing itself when you compute wing area using its technical definition.

Wing area is a "reference area". Whether it reflects the size of the wing or not is irrelevant. What is relevant is that it is computed in a simple and universally consistent way -- so anyone will do it the same way and arrive with the same number. It is used in conjunction with lift/drag numbers and Drag co-efficient numbers in equations to arrive at lift and drag figures. [see illustration]

Two different planforms with two different wing areas.
Image
An extreme example showing how 90% of wing area can have nothing to do with the wing.
Image
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Unread post05 Jul 2008, 19:50

Dwightlooi,

Good points. I think the whole question of F-35 maneuverability is silly anyway. It's been clear that the design was required to have F-16 and F/A-18 like maneuverability or better. Both of which are highly maneuverable and have proven this many times on aerobatic teams and in combat. It's not like they are going to take off in the F-35 and be surprised to discover it can't turn. This is just another one of the completely baseless criticisms of the F-35 that flood the internet because too many people do not understand enough of the details.

Even if the F-35 happens to be marginally less maneuverable than some other jet. That would be at the absolute end of the envelope and not as likely to matter as something like a 360 degree spherical EO/IR sensor would or all the other advantages an F-35 brings to the table. Absolute maneuverability is only one of many performance characteristics and you can find many instances of "more maneuverable" jets getting shot down by more capable less maneuverable jets.

-DA
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Unread post05 Jul 2008, 19:53

dwight is correct, but I think the supercritical area rule comparison is a bit of a stretch. Body lift is mostly defined by compression lift (when going fast) and vortex lift (when going slow). The intakes and chinning on the F-35 seem to be acting like a regular LEX like on the hornet or flanker. The shape of the fuselage is probably more a function of oblique area ruling, since a wing planform of a (comparatively) narrow fuselage wouldn't make a huge difference (given how wing efficiency degrades rapidly as a function of span). That is not to say, that the F-35's fuselage wasn't kept broad with some aft "camber" intentionally to delay shocks like a supercritical airfoil. In that respect, stealth (smooth wing-body contours, internal weapons in a broad fuselage and chinning at the nose) could have favorable aerodynamic advantages. With today's computational tools, the whole aircraft becomes an aerodynamic system much more so than early design methodology, which would just isolate the wings and other components (for the most part). This also means that it's much harder to discern such details by looking at the planform and shape.

Assuming the F-35 will be a poor aerodynamic performer would be quite premature.
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